0
Research Papers: Micro/Nanoscale Heat Transfer

Selecting Optimal Parallel Microchannel Configuration(s) for Active Hot Spot Mitigation of Multicore Microprocessors in Real Time

[+] Author and Article Information
Lakshmi Sirisha Maganti

Department of Mechanical Engineering,
Indian Institute of Technology Madras,
Chennai 600036, India
e-mail: lakshmisirisha.maganti@gmail.com

Purbarun Dhar

Department of Mechanical Engineering,
Indian Institute of Technology Ropar,
Rupnagar 140001, India
e-mail: purbarun@iitrpr.ac.in

T. Sundararajan

Department of Mechanical Engineering,
Indian Institute of Technology Madras,
Chennai 600036, India
e-mail: tsundar@iitm.ac.in

Sarit K. Das

Department of Mechanical Engineering,
Indian Institute of Technology Madras,
Chennai 600036, India;
Department of Mechanical Engineering,
Indian Institute of Technology Ropar,
Rupnagar 140001, India
e-mail: skdas@iitrpr.ac.in

1Corresponding authors.

Manuscript received July 6, 2016; final manuscript received April 27, 2017; published online May 23, 2017. Editor: Portonovo S. Ayyaswamy.

J. Heat Transfer 139(10), 102401 (May 23, 2017) (11 pages) Paper No: HT-16-1443; doi: 10.1115/1.4036643 History: Received July 06, 2016; Revised April 27, 2017

Design of effective microcooling systems to address the challenges of ever increasing heat flux from microdevices requires deep examination of real-time problems and has been tackled in depth. The most common (and apparently misleading) assumption while designing microcooling systems is that the heat flux generated by the device is uniform, but the reality is far from this. Detailed simulations have been performed by considering nonuniform heat load employing the configurations U, I, and Z for parallel microchannel systems with water and nanofluids as the coolants. An Intel® Core i7-4770 3.40 GHz quad core processor has been mimicked using heat load data retrieved from a real microprocessor with nonuniform core activity. This study clearly demonstrates that there is a nonuniform thermal load induced temperature maldistribution along with the already existent flow maldistribution induced temperature maldistribution. The suitable configuration(s) for maximum possible overall heat removal for a hot zone while maximizing the uniformity of cooling have been tabulated. An Eulerian–Lagrangian model of the nanofluids shows that such “smart” coolants not only reduce the hot spot core temperature but also the hot spot core region and thermal slip mechanisms of Brownian diffusion and thermophoresis are at the crux of this. The present work conclusively shows that high flow maldistribution leads to high thermal maldistribution, as the common prevalent notion is no longer valid and existing maldistribution can be effectively utilized to tackle specific hot spot location, making the present study important to the field.

FIGURES IN THIS ARTICLE
<>
Copyright © 2017 by ASME
Your Session has timed out. Please sign back in to continue.

References

Tuckerman, D. B. , and Pease, R. F. W. , 1981, “ High-Performance Heat Sinking for VLSI,” IEEE Electron Device Lett., 2(5), pp. 126–129. [CrossRef]
Sasaki, S. , and Kishimoto, T. , 1986, “ Optimal Structure for Microgrooved Cooling Fin for High-Power LSI Devices,” Electron. Lett., 22(25), pp. 1332–1334. [CrossRef]
Kishimoto, T. , and Sasaki, S. , 1987, “ Cooling Characteristics of Diamond-Shaped Interrupted Cooling Fin for High-Power LSI Devices,” Electron. Lett., 23(9), pp. 456–457. [CrossRef]
Peng, X. F. , Peterson, G. P. , and Wang, B. X. , 1994, “ Frictional Flow Characteristics of Water Flowing Through Rectangular Microchannels,” Exp. Heat Transfer, 7(4), pp. 249–264. [CrossRef]
Judy, J. , Maynes, D. , and Webb, B. W. , 2002, “ Characterization of Frictional Pressure Drop for Liquid Flows Through Microchannels,” Int. J. Heat Mass Transfer, 45(17), pp. 3477–3489. [CrossRef]
Kandlikar, S. G. , 2012, “ History, Advances, and Challenges in Liquid Flow and Flow Boiling Heat Transfer in Microchannels: A Critical Review,” ASME J. Heat Transfer, 134(3), p. 034001. [CrossRef]
Kandlikar, S. G. , 2005, “ High Flux Heat Removal With Microchannels—A Roadmap of Challenges and Opportunities,” Heat Transfer Eng., 26(8), pp. 5–14. [CrossRef]
Kumaraguruparan, G. , ManikandaKumaran, R. , Sornakumar, T. , and Sundararajan, T. , 2011, “ A Numerical and Experimental Investigation of Flow Maldistribution in a Micro-Channel Heat Sink,” Int. Commun. Heat Mass Transfer, 38(10), pp. 1349–1353. [CrossRef]
Siva, M. V. , Pattamatta, A. , and Das, S. K. , 2014., “ Effect of Flow Maldistribution on the Thermal Performance of Parallel Microchannel Cooling Systems,” Int. J. Heat Mass Transfer, 73, pp. 424–428. [CrossRef]
Maganti, L. S. , Dhar, P. , Sundararajan, T. , and Das, S. K. , 2016, “ Particle and Thermohydraulic Maldistribution of Nanofluids in Parallel Microchannel Systems,” Microfluid. Nanofluid., 20(109), pp. 1–16.
Siva, M. V. , Pattamatta, A. , and Das, S. K. , 2014, “ Investigation on Flow Maldistribution in Parallel Microchannel Systems for Integrated Microelectronic Device Cooling,” IEEE Trans. Compon. Packag. Manuf. Technol., 4(3), pp. 438–450. [CrossRef]
Hetsroni, G. , Mosyak, A. , and Segal, Z. , 2011, “ Nonuniform Temperature Distribution in Electronic Devices Cooled by Flow in Parallel Microchannels,” IEEE Trans. Compon. Packag. Manuf. Technol., 24(1), pp. 16–23.
Nielsen, K. K. , Engelbrecht, K. , Christensen, D. V. , Jensen, J. B. , Smith, A. , and Bahl, C. R. H. , 2012, “ Degradation of the Performance of Microchannel Heat Exchangers Due to Flow Maldistribution,” Appl. Therm. Eng., 40, pp. 236–247. [CrossRef]
Li, J. , and Kleinstreuer, C. , 2008, “ Thermal Performance of Nanofluid Flow in Microchannels,” Int. J. Heat Fluid Flow, 29(4), pp. 1221–1232. [CrossRef]
Escher, W. , Brunschwiler, T. , Shalkevich, N. , Shalkevich, A. , Burgi, T. , Michel, B. , and Poulikakos, D. , 2011, “ On the Cooling of Electronics With Nanofluids,” ASME J. Heat Transfer, 133(5), p. 051401. [CrossRef]
Lee, J. , and Mudawar, I. , 2007, “ Assessment of the Effectiveness of Nanofluids for Single-Phase and Two-Phase Heat Transfer in Micro-Channels,” Int. J. Heat Mass Transfer, 50(3), pp. 452–463. [CrossRef]
Maganti, L. S. , Dhar, P. , Sundararajan, T. , and Das, S. K. , 2015, “ Thermally ‘Smart’ Characteristics of Nanofluids in Parallel Microchannel Systems to Mitigate Hot Spots in MEMS,” IEEE Trans. Compon. Packag. Manuf. Technol., 6(12), pp. 1834–1846. [CrossRef]
Das, S. K. , Putra, N. , Thiesen, P. , and Roetzel, W. , 2003, “ Temperature Dependence of Thermal Conductivity Enhancement for Nanofluids,” ASME J. Heat Transfer, 125(4), pp. 567–574. [CrossRef]
Cho, E. S. , Choi, J. W. , Yoon, J. S. , and Kim, M. S. , 2010, “ Experimental Study on Microchannel Heat Sinks Considering Mass Flow Distribution With Non-Uniform Heat Flux Conditions,” Int. J. Heat Mass Transfer, 53, pp. 2159–2168. [CrossRef]
Sharma, C. S. , Schlottig, G. , Brunschwiler, T. , Tiwari, M. K. , Michel, B. , and Poulikakos, D. , 2015, “ A Novel Method of Energy Efficient Hotspot-Targeted Embedded Liquid Cooling for Electronics: An Experimental Study,” Int. J. Heat Mass Transfer, 88, pp. 684–694. [CrossRef]
Sharma, C. S. , Tiwari, M. K. , and Poulikakos, D. , 2016, “ A Simplified Approach to Hotspot Alleviation in Microprocessors,” Appl. Therm. Eng., 93, pp. 1314–1323. [CrossRef]

Figures

Grahic Jump Location
Fig. 1

Exploded view of the computational domain and arrangement of heaters to mimic a real-time microprocessor and its nonuniform heat release. The arrangement of components of the microprocessor (for a quad core Intel Nehalem® generation 1 architecture), such as the computational core, the cache memory, and I/O bus, has been shown on the microprocessor.

Grahic Jump Location
Fig. 2

Effects of nonuniform thermal load on the performance of PMCS (active heater at 10 W and rest at 2.5 W, as mapped from a real-time microprocessor): (a) U configuration, (b) I configuration, and (c) Z configuration

Grahic Jump Location
Fig. 3

Representation of temperature patterns and hot spot locations for both uniform and nonuniform thermal loads (single heater) in U configuration. The dotted circle represents the peak load heater position.

Grahic Jump Location
Fig. 4

Representation of temperature patterns and hot spot locations for both uniform and nonuniform thermal loads (single heater) in I configuration. The dotted circle represents the peak load heater position.

Grahic Jump Location
Fig. 5

Representation of temperature patterns and hot spot locations for both uniform and nonuniform thermal loads (single heater) in Z configuration. The dotted circle represents the peak load heater position.

Grahic Jump Location
Fig. 6

Comparison of thermal performance of water and alumina–water (5 vol %) nanofluids as heat transfer fluids in parallel microchannel cooling systems under nonuniform thermal load: (a) U configuration, (b) I configuration, and (c) Z configuration

Grahic Jump Location
Fig. 7

Proposed flow configuration(s) for thermal safety of device based on location of active heat source (single active heater). The values represent the corresponding figure of merit. The hot spot locations shown in the first column correspond to the flow direction as shown in the table heading.

Grahic Jump Location
Fig. 8

Figure of Merit of each configuration for known working parameters

Grahic Jump Location
Fig. 9

Effect of nonuniform thermal load on thermal performance of water and alumina–water based PMCS when two heaters (simulating a real processor physical core) are active: (a) U configuration, (b) I configuration, and (c) Z configuration

Grahic Jump Location
Fig. 10

Proposed cooling configurations depending on location of active heat sources (two active heaters) mimicking the physical core of an Intel® Core i7-4770 3.40 GHz processor

Grahic Jump Location
Fig. 11

Thermal contours of U configuration using water and nanofluids as working fluids: (a) and (a1) when H5 heater is active and (b) and (b1) when H7 heater is active. The reduction in temperature as well as hot spot size is markedly visible. (c) Percentage reduction in hot spot core size using nanofluids with respect to water as working fluids.

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In